Well, maybe these will help....
Here's our barred rock as a chick:
and Australorp:
The barred rock a little older (middle of pic, with the Australorp in the foreground)
and our Silver Laced Wyandotte
I think you will have to wait a couple weeks and then take some closer pics, in good light, of the chicks you're unsure of... side view showing feet & legs, and good pics of the head and combs. Post the pics here and people can help you figure it out!!
by the way, our Black Australorp hen is...